diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2d759056..8d2ee9c9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -624,7 +624,7 @@ jobs:
       - name: mingw64
         if: ${{ matrix.msystem == 'mingw64' }}
         run: |
-          PATH=/mingw64/bin:$PATH /mingw32/bin/mingw32-make clean test MOREFLAGS=-Werror
+          PATH=/mingw64/bin:$PATH /mingw32/bin/mingw32-make clean test gcc-og-test MOREFLAGS=-Werror
           PATH=/mingw64/bin:$PATH /mingw32/bin/mingw32-make -C tests/bench
           # Abort if result of "file ./xxhsum.exe" doesn't contain 'x86-64'.
           # Expected output is "./xxhsum.exe: PE32+ executable (console) x86-64, for MS Windows"
diff --git a/Makefile b/Makefile
index cf94286c..46d30221 100644
--- a/Makefile
+++ b/Makefile
@@ -361,7 +361,7 @@ clangtest: clean
 .PHONY: gcc-og-test
 gcc-og-test: clean
 	@echo ---- test gcc -Og compilation ----
-	CFLAGS="-Og -Wall -Wextra -Wundef -Wshadow -Wcast-align -Werror -fPIC" MOREFLAGS="-Werror" $(MAKE) all
+	CFLAGS="-Og -Wall -Wextra -Wundef -Wshadow -Wcast-align -Werror -fPIC" CPPFLAGS="-DXXH_NO_INLINE_HINTS" MOREFLAGS="-Werror" $(MAKE) all
 
 .PHONY: cxxtest
 cxxtest: clean
diff --git a/README.md b/README.md
index de0ece67..806c902f 100644
--- a/README.md
+++ b/README.md
@@ -157,7 +157,7 @@ The following macros can be set at compilation time to modify `libxxhash`'s beha
                          Defining this macro to 1 will mark all internal functions as `static`, allowing the compiler to decide whether to inline a function or not.
                          This is very useful when optimizing for smallest binary size,
                          and is automatically defined when compiling with `-O0`, `-Os`, `-Oz`, or `-fno-inline` on GCC and Clang.
-                         This might also increase performance depending on compiler and architecture.
+                         It may also be required to successfully compile using `-Og`, depending on compiler version.
 - `XXH_SIZE_OPT`: `0`: default, optimize for speed
                   `1`: default for `-Os` and `-Oz`: disables some speed hacks for size optimization
                   `2`: makes code as small as possible, performance may cry